Thanks, Will. I took a look at some of this, and have some questions 
about your system entities. You have both 'item' and 'component' defined as:

Item:
· a discoverable unit in the digital repository.
· An item contains 0 or more components.
· If an item contains 1 or more components, it must also contain a 
structural metadata record.
· An item must contain one or more descriptive metadata records.
· An item is typed; the item type determines what components are valid.
· An item may have relationships with other items; ie. [item A] 
isMemberOfCollection [item B]
· An item will be assigned a status: Incomplete, Complete, Published, etc.
An item can be qualified with arbitrary indicators ("Needs translation") 
that relate to the workflow of a
given project.

Component:
· an atomic unit of digital content. For example, an image, a page of a 
book, a text document, a pdf.
  A component contains a bitstream representing the content, or a URI 
pointing to a bitstream, as well as
administrative metadata for the bitstream.

This may need further explanation, as I am puzzled about the item being 
typed, but the component not. It seems to be that definition of 'item' 
and 'component' may be in the eye of the beholder, and that at either 
level you would need to be clear about the digital type. It also seems 
that many items will be of more than one type (text and images being a 
prime example, but there is the whole 'kit' concept in description 
cataloging.)

If you'd like discussion to be on the blog, I can paste the question 
into the comments area.

kc

Will Sexton wrote:
> I posted here early in the winter on Duke's plans to develop a 
> software tool to support metadata creation.  Our project has moved 
> forward with the hiring of two programmers and an intensive phase of 
> analysis and design.  We want to share our progress as we go, so I've 
> composed a post with some of our design documents at
>
> http://library.duke.edu/blogs/digital-collections/2009/02/13/on-the-trident-project-part-1-architecture/ 
>
>
> As always we welcome feedback from the code4lib community.  
> Regrettably, we'll not send anyone to the conference next week, but I 
> thought I would use this very nearly calm moment  to report on our 
> progress and invite discussion.
>
> Best,
>
> Will
> -- 
> Will Sexton
> Metadata Analyst / Programmer
> Duke University Libraries
>
>


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Karen Coyle / Digital Library Consultant
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